The Federal Office for Information Security said Wednesday that clicking on an infected PDF file “is sufficient to infect the mobile device with malware without the user’s knowledge” on several versions of Apple’s iOS operating system.

It says the same could occur when opening a website that carries an infected PDF file, possibly opening the device to criminals spying on passwords, planners, photos, text messages, e-mails and even listen in on phone conversations.

The agency says Apple Inc. has not yet offered a patch to fix the problem.

Apple Germany spokesman Georg Albrecht told The Associated Press he was aware of the warning, adding that Apple would not comment on it.